Bronchial Asthma Flashcards
Classify antiasthmatic drugs
- Bronchodilators
a) sympathomimetics
i)selective beta2 adrenergic agonist
ii) nonselective
b)methylxanthines
c)anti-cholinergics - leukotriene receptor antagonist
- mast cell stabilizer
- glucocorticoids
a) inhaled glucocorticoids
b)systemic glucocorticoids - anti IgE mono clonal antibody
Name selected beta 2 adrenergic agonist used for asthma
- Albuterol
- salbutamol 
- Terbutaline
- Bambuterol
- Salmenterol
- Formoterol
Name nonselective sympathomimetic used in asthma
Adrenaline
What is the mechanism of action of sympathomimetics
After by stimulating Beta2 receptors in the bronchial smooth muscles and mast cells. Increase in cAMP. Causes:
1. Bronchodilation
2. inhibits the release of histamine, SRS-A from mast cells
3. promote mucocillary clearance
What are the side effects of selective beta2 adrenergic agonist
- Tremor
- tachycardia
- palpitations
- hypokalaemia
- rarely cardiac arrhythmias
What is the mechanism of action of methylxanthines
The inhibit phosphodiesterase which increases cAMP and cGMP By preventing their degradation. which causes:
1. bronchodilation
2. inhibition of release of histamine and SRS-A from mast cells
3? improves mucocillary clearance and respiratory passages
Name methylxanthines drugs
- Theophylline 
- Aminophylline
- Etophylline
- Doxophylline
What are the adverse effects of methylxanthines
- Tachycardia
- palpitation
- hypotension
- sometimes sudden death due to cardiac arrhythmias
What are the drug interactions of methylxanthines
- Sympathomimetics x methylxanthines Causes bronchodilation and cardiac stimulation as it potentiates the effects of sympathomimetics
- Phenytoin/rifampicin/phenobarbital x theophylline : Are enzyme inducers and interfere with theophylline metabolism.
- Cimetidine /Ciprofloxacin/erythromycin x theophylline: they are enzyme inhibitors, interfering with theophylline metabolism
What are the uses of methylxanthianes 
- Bronchial asthma and COPD
- apnoea in premature infants
Name anticholinergic drugs used in asthma
- Ipratropium bromide
- Tiotropium bromide
What is the mechanism of action of leukotriene antagonist
They blocked effects of cysteinyl leukotrienes on bronchial smooth muscles. Cause:
1. Bronchodilation
2. suppresses bronchial inflammation
3. decreases hypersensitivity
What are the side effects of leukotriene antagonist
- Headache
- skin rashes
- rarely eosinophilia
Which Leukotriene antagonist inhibits 5-Lipooxygenase 
Zileuton
Name leukotriene antagonists
- Montelukast
- Zafirlukast
- Zileuton
Name mast cell stabilizers 
- Sodium cromoglycate
- Ketotifen
What is the mechanism of action of mast cell stabilizer
Inhibit the release of various mediators histamine, LT’s, PG’s, PAF, etc.  by stabilizing the cell membrane
What are the uses of mast cells stabilizers
- Allergic asthma
- Allergic conjunctivitis, allergic rhinitis, allergic dermatitis etc.
What are the adverse effects of mast cell stabilizers
- Cough
- bronchospasm
- headache
- nasal congestion
Name systemic and inhaled glucocorticoids
systemic:
1. Hydrocortisone (cortisol) 
2. Prednisolone
3. methylprednisolone
Inhalation:
1. beclomethasone
2. budesonide
3. fluticasone
What is the mechanism of action of glucocorticoids
Glucocorticoids into synthesis of Lipocortin which inhibits phospholipase A2 And there by preventing the formation of various mediator such as PG’s, TXA2 , SRS-As, etc. They:
1. Suppress anti-inflammatory response
2. decrease mucosal oedema
3. reduce bronchial hyperactivity
What are the side effects of glucocorticoids
- Hoarseness of voice
- dysphonia
- oropharyngeal candidiasis
- gastric irritation
- sodium and water retention
- muscle weakness
- osteoporosis
- HPA axis suppression
Name anti-IgE monoclonal antibody
Omalizumab
What is the mechanism of action of anti- IgE mono clonal antibodies
Prevents the binding of IgE to mast cells, preventing mast cell degranulation
What are the side effects of omalizumab
- Redness
- stinging
- itching
- induration
What are the inhalation devices for asthma
- metered dose inhaler
- Dry powder inhalers
- Nebulizers 
Describe the treatment of acute severe asthma
- Administer humidified oxygen
- nebulized beta2 adrenergic agonist (Salbutamol 5 mg/turbutaline 10 mg) and anti-cholinergic agent (Ipratropium bromide 0.5 mg) 
- Systemic glucocorticoids. IV hydrocortisone 200 mg
- IV fluids to correct dehydration
- Potassium supplements to correct hypokalaemia
- Sodium bicarbonate to treat acidosis
- Antibiotics to treat infection
Which drugs should be avoided in patients with bronchial asthma
- NSAIDs Like aspirin, ibuprofen, and diclofenac (paracetamol can be used)
- Beta adrenergic antagonist/blockers
- cholinergic agents
